diff options
Diffstat (limited to 'include/net/netmem.h')
| -rw-r--r-- | include/net/netmem.h | 133 |
1 files changed, 129 insertions, 4 deletions
diff --git a/include/net/netmem.h b/include/net/netmem.h index 8a6e20be4b9d..386164fb9c18 100644 --- a/include/net/netmem.h +++ b/include/net/netmem.h @@ -8,6 +8,7 @@ #ifndef _NET_NETMEM_H #define _NET_NETMEM_H +#include <linux/dma-mapping.h> #include <linux/mm.h> #include <net/net_debug.h> @@ -20,15 +21,33 @@ DECLARE_STATIC_KEY_FALSE(page_pool_mem_providers); */ #define NET_IOV 0x01UL +enum net_iov_type { + NET_IOV_DMABUF, + NET_IOV_IOURING, + + /* Force size to unsigned long to make the NET_IOV_ASSERTS below pass. + */ + NET_IOV_MAX = ULONG_MAX +}; + struct net_iov { - unsigned long __unused_padding; + enum net_iov_type type; unsigned long pp_magic; struct page_pool *pp; - struct dmabuf_genpool_chunk_owner *owner; + struct net_iov_area *owner; unsigned long dma_addr; atomic_long_t pp_ref_count; }; +struct net_iov_area { + /* Array of net_iovs for this area. */ + struct net_iov *niovs; + size_t num_niovs; + + /* Offset into the dma-buf where this chunk starts. */ + unsigned long base_virtual; +}; + /* These fields in struct page are used by the page_pool and net stack: * * struct { @@ -54,6 +73,16 @@ NET_IOV_ASSERT_OFFSET(dma_addr, dma_addr); NET_IOV_ASSERT_OFFSET(pp_ref_count, pp_ref_count); #undef NET_IOV_ASSERT_OFFSET +static inline struct net_iov_area *net_iov_owner(const struct net_iov *niov) +{ + return niov->owner; +} + +static inline unsigned int net_iov_idx(const struct net_iov *niov) +{ + return niov - net_iov_owner(niov)->niovs; +} + /* netmem */ /** @@ -72,6 +101,22 @@ static inline bool netmem_is_net_iov(const netmem_ref netmem) return (__force unsigned long)netmem & NET_IOV; } +/** + * __netmem_to_page - unsafely get pointer to the &page backing @netmem + * @netmem: netmem reference to convert + * + * Unsafe version of netmem_to_page(). When @netmem is always page-backed, + * e.g. when it's a header buffer, performs faster and generates smaller + * object code (no check for the LSB, no WARN). When @netmem points to IOV, + * provokes undefined behaviour. + * + * Return: pointer to the &page (garbage if @netmem is not page-backed). + */ +static inline struct page *__netmem_to_page(netmem_ref netmem) +{ + return (__force struct page *)netmem; +} + /* This conversion fails (returns NULL) if the netmem_ref is not struct page * backed. */ @@ -80,7 +125,7 @@ static inline struct page *netmem_to_page(netmem_ref netmem) if (WARN_ON_ONCE(netmem_is_net_iov(netmem))) return NULL; - return (__force struct page *)netmem; + return __netmem_to_page(netmem); } static inline struct net_iov *netmem_to_net_iov(netmem_ref netmem) @@ -103,6 +148,17 @@ static inline netmem_ref page_to_netmem(struct page *page) return (__force netmem_ref)page; } +/** + * virt_to_netmem - convert virtual memory pointer to a netmem reference + * @data: host memory pointer to convert + * + * Return: netmem reference to the &page backing this virtual address. + */ +static inline netmem_ref virt_to_netmem(const void *data) +{ + return page_to_netmem(virt_to_page(data)); +} + static inline int netmem_ref_count(netmem_ref netmem) { /* The non-pp refcount of net_iov is always 1. On net_iov, we only @@ -127,6 +183,22 @@ static inline struct net_iov *__netmem_clear_lsb(netmem_ref netmem) return (struct net_iov *)((__force unsigned long)netmem & ~NET_IOV); } +/** + * __netmem_get_pp - unsafely get pointer to the &page_pool backing @netmem + * @netmem: netmem reference to get the pointer from + * + * Unsafe version of netmem_get_pp(). When @netmem is always page-backed, + * e.g. when it's a header buffer, performs faster and generates smaller + * object code (avoids clearing the LSB). When @netmem points to IOV, + * provokes invalid memory access. + * + * Return: pointer to the &page_pool (garbage if @netmem is not page-backed). + */ +static inline struct page_pool *__netmem_get_pp(netmem_ref netmem) +{ + return __netmem_to_page(netmem)->pp; +} + static inline struct page_pool *netmem_get_pp(netmem_ref netmem) { return __netmem_clear_lsb(netmem)->pp; @@ -158,12 +230,43 @@ static inline netmem_ref netmem_compound_head(netmem_ref netmem) return page_to_netmem(compound_head(netmem_to_page(netmem))); } +/** + * __netmem_address - unsafely get pointer to the memory backing @netmem + * @netmem: netmem reference to get the pointer for + * + * Unsafe version of netmem_address(). When @netmem is always page-backed, + * e.g. when it's a header buffer, performs faster and generates smaller + * object code (no check for the LSB). When @netmem points to IOV, provokes + * undefined behaviour. + * + * Return: pointer to the memory (garbage if @netmem is not page-backed). + */ +static inline void *__netmem_address(netmem_ref netmem) +{ + return page_address(__netmem_to_page(netmem)); +} + static inline void *netmem_address(netmem_ref netmem) { if (netmem_is_net_iov(netmem)) return NULL; - return page_address(netmem_to_page(netmem)); + return __netmem_address(netmem); +} + +/** + * netmem_is_pfmemalloc - check if @netmem was allocated under memory pressure + * @netmem: netmem reference to check + * + * Return: true if @netmem is page-backed and the page was allocated under + * memory pressure, false otherwise. + */ +static inline bool netmem_is_pfmemalloc(netmem_ref netmem) +{ + if (netmem_is_net_iov(netmem)) + return false; + + return page_is_pfmemalloc(netmem_to_page(netmem)); } static inline unsigned long netmem_get_dma_addr(netmem_ref netmem) @@ -171,4 +274,26 @@ static inline unsigned long netmem_get_dma_addr(netmem_ref netmem) return __netmem_clear_lsb(netmem)->dma_addr; } +void get_netmem(netmem_ref netmem); +void put_netmem(netmem_ref netmem); + +#define netmem_dma_unmap_addr_set(NETMEM, PTR, ADDR_NAME, VAL) \ + do { \ + if (!netmem_is_net_iov(NETMEM)) \ + dma_unmap_addr_set(PTR, ADDR_NAME, VAL); \ + else \ + dma_unmap_addr_set(PTR, ADDR_NAME, 0); \ + } while (0) + +static inline void netmem_dma_unmap_page_attrs(struct device *dev, + dma_addr_t addr, size_t size, + enum dma_data_direction dir, + unsigned long attrs) +{ + if (!addr) + return; + + dma_unmap_page_attrs(dev, addr, size, dir, attrs); +} + #endif /* _NET_NETMEM_H */ |